Question

这是我的代码。我正在尝试从Rust subreddit获得帖子。我将使用Actix的内置客户端，但在Windows上无法使用，因此改用reqwest：

use actix_web::{self, middleware, web, App, HttpRequest, HttpServer};
use futures::future::Future;
use reqwest::{
    self,
    r#async::{Client},
};

fn get_rust_posts(
    _req: HttpRequest,
    client: web::Data<Client>,
) -> impl Future<Item = String, Error = reqwest::Error> {

    client
        .get("http://www.reddit.com/r/rust.json")
        .send()
        .and_then(|mut resp| resp.text())
        .map_err(|err| {
            println!("Error in get rust posts: {}", err);
            err
        })
}

fn main() {
    let mut server = HttpServer::new(|| {
        App::new()
            .data(Client::new())
            .wrap(middleware::Logger::default())
            .service(web::resource("/get/rust/posts").route(web::get().to_async(get_rust_posts)))
    });
    server.bind(("0.0.0.0", 8000)).unwrap().run().unwrap();
}

[dependencies]
actix-web = "1.0.8"
futures = "0.1.29"
reqwest = "0.9.21"

这是错误：

error[E0277]: the trait bound `fn(actix_web::request::HttpRequest, actix_web::data::Data<reqwest::async_impl::client::Client>) -> impl futures::future::Future 
{get_rust_posts}: actix_web::handler::AsyncFactory<_, _>` is not satisfied
  --> src\main.rs:29:72
   |
29 |             .service(web::resource("/get/rust/posts").route(web::get().to_async(get_rust_posts)))
   |                                                                        ^^^^^^^^ the trait `actix_web::handler::AsyncFactory<_, _>` is not implemented for 
`fn(actix_web::request::HttpRequest, actix_web::data::Data<reqwest::async_impl::client::Client>) -> impl futures::future::Future {get_rust_posts}

Answer 1

to_async需要一个处理程序功能，该功能实现特征AsyncFactory。将Future的{{1}}更改为Item并将actix_web::HttpResponse请求放入reqwest中即可满足该约束。

我还以较慢的响应速度对此进行了测试，尽管actix_web::web::block中有“ block”一词，它似乎可以处理并发请求，我认为这是因为处理程序本身是异步的。

actix_web::web::block

如何解决“ actix_web :: handler :: AsyncFactory <_，_>未实现”错误？

1 个答案: